Traditional incandescent light bulbs are currently being replaced by other light sources having higher energy efficiency and less environmental impact. Alternative light sources include light emitting diode (LED) devices and fluorescent light sources. However, LED devices are relative expensive and complicated to fabricate and fluorescent light sources are known to contain mercury, thereby posing potential health problems due to the health risks involved in mercury exposure. Furthermore, as a result of the mercury content, recycling of fluorescent light sources is both complicated and costly.
An attractive alternative light source has emerged in the form of field emission lighting. A traditional field emission lighting arrangement comprises an anode structure and a field emission cathode, the anode structure consists of a transparent electrically conductive layer and a light conversion layer, such as a layer of phosphor coated on the inner surface of an evacuated envelope, provided in the form of e.g. a transparent glass tube. The phosphor layer emits light when excited by the electrons emitted from the cathode.
Previously known field emission lighting arrangements are often in the shape of tubes and seldom in the form of the traditional bulb. Hence there is a need to provide field emission lighting arrangements with a form factor suitable for retrofitting of e.g. traditional incandescent bulbs as well as corresponding compact fluorescent light sources.